The 25-year-old's fortunes at club level have slumped ever since a possible move from West Bromwich Albion to Tottenham Hotspur fell through in 2015.
However, a decision to play for Burundi, having represented England at several youth levels, has given his career a new dimension.
Berahino, whose side face three-times champions Nigeria in a Group B match, was born in Burundi but fled the country aged 10 along with his mother after his father was killed in civil strife.
He was given refugee status in Britain, where he began his career at West Brom, played for England at under-21 level and was even called up to the senior squad before his early promise was blighted by disciplinary problems.
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Berahino was given clearance by FIFA to represent Burundi in August and made his debut the following month in qualifier against Gabon, scoring in a 1–1 draw.
"I managed to play for England from under-16 to under-21 but Burundi has always been my homeland and I've always wanted to play for Burundi," he told reporters on Friday.
Burundi went on to qualify unbeaten, finishing second behind Mali in their group with two wins and four draws, and securing their place with a nervy 1-1 draw at home to Gabon - a moment he still remembers vividly.
"The day we qualified, you could see for the first time in the history of Burundi people united together, celebrating together, the whole town was going crazy for two or three days, and you could see the smile on their faces," he said.
"Being able to captain Burundi for the first time in such a tournament is a massive honour for me... there is a lot on my shoulders but with the experience I've gained in Europe, I'm sure I can pass it down to my team mates."
Berahino said that discipline had brought Burundi this far. "That's why we all respect each other and all live together as brothers and that's why we are here because of the unity we have," he said.
Having become used to Burundi being labelled as underdogs from the outset, he said the lack of pressure on the team and their unknown qualities would be to their advantage.
"They don't know us, they probably don't watch our games, so that releases the pressure on us so we can play without any fear at all," he said.
"That's we managed to show in the qualification and that's why we went through the whole qualification unbeaten."
"We are not going to let them walk all over us; we will stand up like we did qualifying and let the best team win."
(Writing by Brian Homewood; Editing by Christian Radnedge)
